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nickwoolley

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Ghosting with Monitor Extension Cable

I've relocated a PC to be remote from it's monitor so I had to install a 5m monitor extension cable, however it caused severe ghosting. I managed to fit a 3m extension cable instead which improved the situation but the display quality is still poor. Is there a big difference in the quality of extension cables? Is there a specification of cable I should use to avoid this reduction in performance?
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Luc Franken
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If you really have to use an extension cable, don't be cheap on it, it'll only give you problems, you'll need a shielded cable and of really good quality, especially if you want to use high resolutions and a high refresh rate.

LucF
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jhance

Indeed there are HUGE differences in quality.  You have a impedance mismatch and that produces reflections on the cable.  Visually that produces "ghosting" of the real image on the display.

The solution here is to get a top-quality video extension cable.

Try http://www.blackbox.com
Absolutely.. what Lucf said.  Don't go cheap on monitor extension cabling.. we used to run a vga splitter box and had exactly the problems you're reporting until we purchased better quality cabling.

Also, I believe the maximum length for a DB-15 VGA cable is six feet.
But if you really need the extra length, follow above suggestions.
Personally I needed one to use in a disco I worked about 5 years ago, it had to be 25 meters long. It costs over € 150.= but AFAIK it still is working there. We used it to project all kind of video on a screen behind the DJ.
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How do you judge the quality when buying over the internet. It needs to be shielded, is there any other specification to look for?
nickwoolley, I suggest you don't buy these kind of things over the internet. Just go to your local store and see what they've got there, ask them if it's possible to return the cable if it doesn't satisfies you. If they don't agree with that, go to another store.

Most good cables are shielded and have gold connectors. Just look for that.
I suggest you DO buy one of these over the internet.  The video extension cables you'll find from BlackBox, albeit expensive, are simply the best made anywhere.  I've used them for years in many different lengths and they are excellent.  You'll NOT find good video extension cables at any local shop.  These shops typically carry cheap consumer junk cables and that is likely exactly what you have now.  The BlackBox cables are first rate and 100% guaranteed by them.
Sorry jhance, but I really don't agree with you...
In the city I live we have shops that sell these kind of professional cables, they don't sell cheap garbage wich you you can find in every computer shop. And I do think they'll help you much more if you have troubles than some kind of internet shop. I have to say that BlackBox cables are very good, but I personally still prefer to go to a shop where they can show me how good their cables are and for what distance what cable satisfies my needs.

> are simply the best made anywhere
How would you know, have you tried every cable you can find in the world?? I think not...
I'm experssing MY opinion and MY experience.  You may keep your smart remarks to yourself please.
And I'm not allowed to give MY opinion? Strange, I can't find any of that in the MA..
jhance: I'm in the UK, I found their UK site but the search didn't find any VGA extension cables.

LucF: The only shop around here is PC World and personaly I get the feelings of frustration as soon as I step throught their door.

 I bought the previous cable from eBuyer.com, it was a cheap Belkin VGA Monitor Extension Cable HDDB15 Male > Female 5m at £2.78 . I see they do a Belkin High Integrity VGA/SVGA Monitor Extension Cable 3m at £17.63, this is double shielded and has gold-plated connectors - I'll try it. Belkin support suggest the problem would be caused by a weak signal from the display adaptor.

 
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Luc Franken
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> And I'm not allowed to give MY opinion? Strange, I can't find any of that in the MA..

You ARE allowed to give your opinion but not about ME!

To quote:

"How would you know, have you tried every cable you can find in the world?? I think not..."
I just tried to say that there might be other cables as good as the ones from BlackBox or maybe even better. I wasn't trying to insult you. Next time I'll put a smily after "I think not..." to show that is was meant as a joke.
Back to the topic at hand...

You can get some reasonably priced and professional quality cables at http://www.markertek.com .  I also have a Kramer VP-300 distribution amp which will boost the signal voltage to accomodate long runs - I have 30-ft vga run at home.
As was said above, a $2.78 VGA extension is not a lot to spend on a cable, and will cause problems.
A single good quality cable should take care of it. In my home theater room the PC is about 50'  (~18m) from the computer, and a single high quality VGA extension purchased at a local shop for about $65can, (where they would let me try them first) did the job with no signs of ghosting. I've also done a few installations of longer distance, but the cost on the cable was to great, so I went with a VGA to Cat5 Converter. such as http://www.videocapturecard.com/vgacat5.html 
In your situation of only going 5m, a good cable is the way to go, but if the need to go further exists, a extender can work up to 50-60m at XGA resolution.
Many online VGA extension sales sites provide technical specs on there cables, and a good quality 15' extenstion shouldn't run you more than $20-$25usd.

Just a bit more info.

SD
I've ordered a Belkini 'high integrety' cable for about £15 with gold plated connectors, it should be here tomorrow, if it is I'll let you know and conclude this thread.
Sorry I missed seeing this one. The Belkin cable with gold connections solved the problem (although not perfect).
I was going to award the point to LucF but there's no accept button!
I see why, it's an old closed account.